β-Substituted polyfluoroethyl compounds

ABSTRACT

β-Substituted polyfluoroethyl compounds, process for the preparation thereof, copolymers thereof, compound intermediates, and process therefor. The copolymers are useful as ion exchange resins or structural foams.

FIELD OF THE INVENTION

This invention relates to β-substituted polyfluoroethyl compounds, aprocess for their preparation, polymers prepared from them, compoundintermediates, and a process for preparing the intermediates.

BACKGROUND INFORMATION

U.S. Pat. No. 2,988,537 discloses the following reaction: ##STR1##wherein X is halogen, M is alkali metal and R¹ and R³ are alkyl orfluorinated alkyl having up to 18 carbon atoms; R² is defined as R¹ butlimited to 12 carbon atoms.

U.S. Pat. No. 3,091,643 discloses the following reaction:

    R.sub.x CO.sub.2 R+MOR.sup. →R.sub.x C(OM)(OR.sup.1)(OR)

    (R.sub.x).sub.2 C(OM)OR→(R.sub.x).sub.2 CO

wherein R_(x) is a monovalent polyfluoroperhalocarbyl orω-hydroperfluoroperhalocarbyl radical; R and R¹ are hydrocarbyl havingup to eight carbon atoms and M is alkali metal.

U.S. Pat. No. 4,238,416 discloses conversion of fluorinated epoxides,##STR2## to carbonyl compounds such as R_(F) C(O)CF₃, R_(F) C(O)CF₂R_(F) and (R_(F))₂ CFC(O)R_(F) wherein R_(F) is perfluoroalkyl orω-hydroperfluoroalkyl and R¹ --R³ are --R_(F) or --F.

U.S. Pat. Nos. 3,513,203 and 3,683,027 disclose preparation ofpolyfluorinated ketones by photochemical combination of liquid C₃ F₆with oxygen and heating the resulting perfluoropolyethers having acidfluoride end groups.

U.S. Pat. Nos. 4,214,070 and 4,160,780 disclose preparation ofketoperfluorosulfonic acids having the formula R_(F) ¹ CF₂C(O)CF(R_(F))SO₂ H and esters thereof, wherein R¹ F and R_(F) are --R orC₁₋₄ perfluoroalkyl, and their use as comonomers.

U.S.S.R. Pat. No. 438,636 discloses compounds having the formula ROCF₂CF₂ C(O)CF(CF₃)OR, wherein R is a fluorinated aliphatic, alicyclic oraromatic group, which are prepared from perfluoro-β-substitutedpropionate salts.

U.K. Patent Application No. 2,051,831 discloses the fluoroketone, RSCF₂CF₂ C(O)CF₂ CF₂ SR, where R is C₁₋₁₀ alkyl (embracing R¹ SCF₂ CF₂ Z whenZ is --C(O)R_(F) X¹ and R_(F) X¹ is --CF₂ CF₂ SR¹) and also disclosesacyl fluorides and vinyl ethers having the respective formulasRZ(CF₂)₃₋₅ [OCF(CF₃)CF₂ ]₀₋₅ OCF(CF₃)COF and RZ(CF₂)₃₋₅ [OCF(CF₃)CF₂]₀₋₅ OCF═CF₂ wherein Z is --S-- or --SO₂ -- and R is C₁₋₁₀ alkyl.

European Patent Application 41,736 discloses compounds of the formula,Y(CF₂)_(a) (CFR_(F))_(b) C(O)R'_(F), wherein Y includes --SO₂ R, --SO₂F, --SO₂ Cl; R is H, alkyl or aryl; a and b are, independently, 0 orintegers, and R_(F) and R'_(F) are, independently, F, Cl, perfluoroalkylor fluorochloroalkyl. This formula embraces XCF₂ CFYZ when X is --SO₂R¹, --SO₂ F or --SO₂ Cl, Y is F or Cl, Z is --C(O)R_(F) X¹ and R_(F) X¹is perfluoroalkyl. An enabling process for preparing the compounds isnot provided.

European Patent Applications Nos. 41,736 and 41,737 disclose compoundsof the formula Y(CF₂)_(a) (CFR_(F))_(b) CFR'_(F) O[CF(CF₂ X)CF₂ O]_(n)CF(CF₂ X')COF and Y(CF₂)_(a) (CFR_(F))_(b) CFR'_(F) O[CF(CF₂ X)CF₂O]_(n) CF═CF₂ where Y is an acid group or a group convertible to an acidgroup; a and b, individually, are 0 or an integer; R_(f) and R'_(f) areeach independently selected from F, Cl, perfluoroalkyl andfluorochloroalkyl; X is F, Cl or Br; and X' is Cl or Br. These compoundsare prepared from an intermediate for which enablement is not provided.These formulae embrace XCF₂ CFYZ when X is --SO₂ R¹, --SO₂ F or --SO₂Cl; Y is F or Cl, Z is --CF(R_(F) X¹)OQ_(n) CF(CF₃)COF or --CF(R_(F)X¹)OQ_(n) CF═CF₂ and R_(F) X' is perfluoroalkyl.

Kalenko et al., Zh. Vses. Khim. O-va, Volume 19, No. 6, 707 (1974)[Chem. Abstr., Volume 82, 97627p (1975)], disclose the followingreaction:

    RCF═CF.sub.2 +R.sup.1 COF→CF.sub.3 CFRC(O)R.sup.1

wherein R is --CF₃, --OCF₃ or --O(CF₂)₂ CF and R¹ is --CF₂ OCF₃, --CF₂CF₂ OCF₃ or (CF₂ CF₂).sub.(1-3) H.

Glazkov et al., Izv. Akad. Nauk SSSR, Ser. Khim, No. 4, page 918 (April1976), disclose preparation of perfluoroether ketones by heatingperfluoroalkylvinyl ethers.

European Patent Application No. 47,945 discloses fluorinated ketosulfonyl fluorides R_(F) C(O)(CF₂)_(n) SO₂ F wherein R_(F) is F or C₁₋₁₀perfluoroalkyl and n is 0 or an integer of 1 to 7.

SUMMARY AND DETAILS OF THE INVENTION

This invention resides in a process for the preparation of aδ-substituted polyfluoroethyl compound, in the polyfluoroethyl compoundand an intermediate, in a process for the preparation of theintermediate and in copolymers of the polyfluoroethyl compound withfluorinated monoolefins.

In the process of the invention a polyfluoroolefin, CF₂ ═CFY, is mixedand reacted with a metal salt, MX² ; and a fluoroester, X¹ R_(F) CO₂ R,and the product intermediate is converted to the β-substitutedpolyfluoroethyl compound. In said process, X¹ is --F, --SR¹, --SO₂ R¹,--CO₂ R, --N₃ or --OR² ;

X² is --SR¹, --N₃, --OC₆ F₅ or --OC₆ H₅ which may be optionallyalkylated;

R is --CH₂ CF₃, --CH₂ (CF₂ CF₂).sub.(1-6) H, --C₆ H₅ or C₁₋₃ alkyl;

R¹ is C₁₋₁₀ alkyl, C₆₋₁₀ aryl or C₆₋₁₀ aralkyl;

M is alkali metal;

Y is --F, --Cl or --OR_(F) ¹ ;

R² is --CH₃, --C₂ H₅ or --C₆ H₅ ;

R_(f) is --CF₂ -- or C₂₋₈ perfluoralkylene, optionally containing onein-chain ether oxygen bond, or two in-chain ether oxygen bonds separatedby at least two carbon atoms; and

R_(F) ¹ is C₁₋₄ perfluoroalkyl.

The intermediate is the compound having the formula XCF₂CFYC(OM)(OR)R_(F) X⁴ wherein X⁴ is X¹ or --C(OR)(OM)CFYCF₂ X wherein Xis --SR¹, --N₃, OC₆ F₅, optionally alkylated --OC₆ H₅, SO₂ R¹, --SO₂ F,or --SO₂ Cl, and X¹, Y, M, R and R_(F) are as defined above. Theintermediate wherein X⁴ is --C(OR)(OM)CFYCF₂ X arises only when adiester reactant is employed.

The β-substituted polyfluoroethyl compound has the formula XCF₂ CFYZwherein

X is --SR¹, --N₃, --OC₆ F₅, optionally alkylated --OC₆ H₅, --SO₂ R¹,--SO₂ F, or --SO₂ Cl;

Y is --F, --Cl or --OR_(F) ¹ ;

Z is selected from --C(O)R_(F) X¹,

--CF(R_(F) X¹)OQ_(n) CF(CF₃)COF,

--CF(R_(F) X¹)OQ_(n) CF(CF₃)CO₂ M¹,

--CF(R_(F) X¹)OQ_(n) CF═CF₂,

--CF(R_(F) X¹)OQ_(m) CF₂ CF═CF₂, and Z¹ R_(F) Z¹ CFYCF₂ X;

Q is --CF(CF₃)CF₂ O--;

M¹ is an alkali metal, alkaline earth metal or ammonium;

n is 0-6;

m is 0-7;

Z¹ is --C(O)--, --CF(OQ_(n) CF(CF₃)COF)--, --CF(OQ_(n) CF(CF₃)CO₂ M¹)--,--CF(OQ_(n) CF═CF₂)--, or --CF(OQ_(m) CF₂ CF═CF₂)--; and

X¹, Y, R¹, R_(F), R_(F) ¹ are as defined above; except that when X is--SR¹, Y is --F, Z is --C(O)R_(F) X¹ and R_(F) is --CF₂ CF₂ --, X¹cannot be --SR¹.

Preferably: X is --SR¹, --SO₂ R¹, --N₃, --OC₆ F₅ or --OC₆ H₅ ; Y is --For --OCF₃ ; X¹ is --F, --N₃, --CO₂ R or --OCH₃ ; R is --CH₃, --CH₂ CF₃or --C₆ H₅ ; R¹ is --CH₃, --C₂ H₅ or --C₆ H₅ ; R_(F) is --CF₂ --, --CF₂CF₂ -- or --CF₂ OCF₂ --; and Z is --C(O)R_(F) X or --C(O)R_(F)C(O)CFYCF₂ X.

The copolymers of the invention have repeat units of the formula:

    --CF.sub.2 CY.sup.1 Y.sup.2 --.sub.(2-300) --(CF.sub.2 CFA).

wherein:

Y¹ is --F or --H;

Y² is --F, --H, --Cl, --R_(F) ¹ or --OR_(F) ¹ ; and

A is --CF₂ Q_(m) OCF(R_(F) X¹)X³,

--Q_(n) OCF(R_(F) X¹)X³, --CF₂ Q_(m) OCF(X³)R_(F) CF(X³)OQ_(m) CF₂CF═CF₂, or --Q_(n) OCF(X³)R_(F) CF(X³)OQ_(n) CF═CF₂, wherein X³ is(CFYCF₂ X) and X, X¹, Y, Q, R_(F), R_(F) ¹, n and m are as definedabove.

In the process for preparing the intermediate compound, the reactantscan be prepared by known techniques and mixed in any order. The relativeamounts of the reactants are not critical. Typically, they areapproximately equimolar. A useful temperature is about -20° to 100° C.,the preferred temperature being about -10° to 50° C. When R is C₁₋₃alkyl, the temperature is preferably about -10° to 15° C. Reaction timecan vary broadly from a few minutes to about a day, the optimum timedepending to a large extent upon the reaction temperature. Reactionpressure is not critical. Pressure of about 25 to 500 psi (170 to 3450kPa) is preferred. The reactants are preferably mixed in a polar aproticsolvent such as dimethyl sulfoxide (DMSO), hexamethylphosphoramide,acetonitrile, tetramethylene sulfone, tetrahydrofuran (THF), tetraglyme,diglyme and dimethylformamide (DMF).

The β-substituted polyfluoroethyl compound of the invention, XCF₂ CFYZ,wherein X is SR¹ ; --N₃, --OC₆ F₅ or OC₆ H₅ which may be optionallyalkylated, and Z is --C(O)R_(F) X¹ or Z¹ R_(F) Z¹ CFYCF₂ X, and Z¹ is--C(O)--, are prepared by treating the intermediate, which need not beisolated from the reaction mixture, with a mineral acid. The acid can beanhydrous, in which case an amount approximately equivalent to theamount of the product is typically added to the reaction mixture,followed by fractionation to collect the ketone. The acid can also beaqueous in which case an excess amount is typically added, followed byextraction with ether, concentration of the extracts, dehydration of theketone hydrate with, for example, P₂ O₅, and fractionation to collectthe polyfluoroethyl compound.

The functional group --SR¹ can be converted to --SO₂ R¹, --SO₂ F or--SO₂ Cl, by known techniques as described, for example, by Ward in J.Org. Chem., Volume 30, 3009 (1965).

The β-substituted polyfluoroethyl compound in which Z is --C(O)R_(F) X¹or --Z¹ R_(F) Z¹ CFYCF₂ X and Z¹ is --C(O)-- can be reacted withhexafluoropropene oxide (HFPO) to form the HFPO adduct or diadduct, thatis, the polyfluoroethyl compound in which Z is --CF(R_(F) X¹)OQ_(n)CF(CF₃)COF or --Z¹ R_(F) Z¹ CFYCF₂ X and Z¹ is --CF(OQ_(n)CF(CF₃)COF)--.

The perfluoroallyl ether, that is, the polyfluoroethyl compound in whichZ is --CF(R_(F) X¹)OQ_(m) CF₂ CF═CF₂ or --Z¹ R_(F) Z¹ CFYCF₂ X and Z¹ is--CF(OQ_(m) CF₂ CF═CF₂)-- can be prepared by reacting the acid fluoride,or an HFPO adduct thereof, with perfluoroallylfluorosulfate orperfluoroallylchloride in the presence of fluoride ions as described,for example, in U.S. Pat. Nos. 4,273,728; 4,273,729; and 4,275,225.

The perfluorovinyl ether, that is, the polyfluoroethyl compound in whichZ is --CF(R_(F) X¹)OQ_(n) CF═CF₂ or --Z¹ R_(F) Z¹ CFYCF₂ X and Z¹ is--CF(OQ_(n) CF═CF₂)-- can be prepared by pyrolyzing the acid fluoridecontaining at least one Q group, and preferably at least two suchgroups, optionally in an aprotic solvent, in the presence of acarbonate, phosphate, sulfite or sulfate salt of an alkali or alkalineearth metal, preferably sodium carbonate or trisodium phosphate.

The perfluorovinyl ether described above wherein Z is --CF(R_(F)X¹)OQ_(n) CF═CF₂ or --Z¹ R_(F) Z¹ CFYCF₂ X and Z¹ is --CF(OQ_(n)CF═CF₂)--, can also be prepared by pyrolyzing, at reduced pressure, thederivative wherein Z is --CF(R_(F) X¹)OQ_(n) CF(CF₃)CO₂ M¹ or --Z¹ R_(F)Z¹ CFYCF₂ X and Z¹ is --CF(OQ_(n) CF(CF₃)CO₂ M¹)--, in the absence ofsolvents or added salts (as in Example 12B). The latter derivatives areprepared by alkaline hydrolysis of the corresponding acyl fluorides.

The β-substituted polyfluoroethyl compounds of the invention whichcontain the fluorinated allyl or vinyl ether-containing groups arecopolymerizable with fluorinated monoolefins such as, for example,tetrafluoroethylene, trifluoroethylene, chlorotrifluoroethylene,vinylidene fluoride and mixtures of tetrafluoroethylene withhexafluoropropene and/or perfluoroalkyl vinyl ethers as described, forexample, in U.S. Pat. Nos. 4,273,728; 4,273,729; and 4,275,225.

The copolymers of the invention, which are moldable into shapedarticles, such as films, have pendant functional groups, X or X¹, whichconfer special utility. When X is --SO₂ R, --SO₂ F, or --SO₂ Cl thecopolymers have ion-exchange properties after hydrolysis, the --SO₂ Rgroups requiring conversion to sulfonates or carboxylates as taught byWard in J. Org. Chem., Volume 30, 3009 (1965). Use of fluoropolymershaving a pendant sulfonate group as ion-exchange membranes is disclosedin U.S. Pat. No. 4,176,215, and as electrolysis cell diaphragm materialsin U.S. Pat. Nos. 4,164,463 and 3,853,720.

Copolymers having pendant --N₃ groups can be converted into chemicallystable, structural foams by heating to a temperature at which N₂ isreleased, the gas serving as a blowing agent.

Such copolymers can also be converted to useful cyano-substitutedcopolymers by reaction of the pendant --CF₂ N₃ groups with a tertiaryphosphine such as triphenylphosphine. The cyano-substituents providecure sites permitting conversion of the copolymers to fluoroelastomersas described in U.S. Pat No. 4,281,092. Copolymers having pendant --OC₆F₅ groups may also be cured to fluoroelastomers as described in U.S.Pat. No. 3,467,638. Copolymers having pendant --CF₂ OC₆ H₅ groups may behydrolyzed in strong aqueous acids to provide pendant --CO₂ H groupswhich, on treatment with aqueous alkali, are converted to carboxylategroups having ion-exchange properties.

EXAMPLES

In the following Examples, which are illustrative of the invention, allparts and percentages are by weight and all temperatures are in degreesCelsius. Table 1 summarizes the various compounds made in the Examples.

                                      TABLE 1                                     __________________________________________________________________________    (1) XCF.sub.2 CFYZ                                                                          (2) XCF.sub.2 CFYC(OM)(OR)R.sub.F X.sup.4                       Example                                                                            X    Y   Z              M R    R.sub.F X.sup.4                           __________________________________________________________________________    1    C.sub.6 H.sub.5 O                                                                  F   COCF.sub.3     Na                                                                              C.sub.6 H.sub.5                                                                    CF.sub.3                                  2    C.sub.6 H.sub.5 O                                                                  OCF.sub.3                                                                         COCF.sub.3     Na                                                                              C.sub.6 H.sub.5                                                                    CF.sub.3                                  3    CH.sub.3 S                                                                         F   COCF.sub.3     Na                                                                              CH.sub.2 CF.sub.3                                                                  CF.sub.3                                  4    CH.sub.3 S                                                                         F   CO(CF.sub.2).sub.2 OCH.sub.3                                                                 Na                                                                              CH.sub.3                                                                           CF.sub.2 CF.sub.2 OCH.sub.3               5    N.sub.3                                                                            F   --             Na                                                                              CH.sub.2 CF.sub.3                                                                  CF.sub.3                                  6    N.sub.3                                                                            F   COCF.sub.3     --                                                                               --   --                                       7    N.sub.3                                                                            F   COC.sub.2 F.sub.5                                                                            --                                                                               --   --                                       8    N.sub.3                                                                            F   CO(CF.sub.2).sub.2 OCH.sub.3                                                                 --                                                                               --   --                                       9    N.sub.3                                                                            F   Z.sup.1 R.sub.F Z.sup.1 CFYCF.sub.2 X                                                        Na                                                                              CH.sub.2 CF.sub.3                                                                  CF.sub.2 OCF.sub.2 C(ONa)--                             Z.sup.1 ═--CO--   (OCH.sub.2 CF.sub.3)CF.sub.2 CF.sub.2                                         N.sub.3                                                 R.sub.F ═--CF.sub.2 OCF.sub.2 --                            10   N.sub.3                                                                            F   CO(CF.sub.2).sub.2 N.sub.3                                                                   Na                                                                              CH.sub.2 CF.sub.3                                                                  CF.sub.2 CF.sub.2 N.sub.3                 11   CH.sub.3 SO.sub.2                                                                  F   COCF.sub.3     --                                                                               --   --                                       12   N.sub.3                                                                            F   CF(CF.sub.3)OOCF(CF.sub.3)COF,                                                               --                                                                               --   --                                                     CF(CF.sub.3)OOCF(CF.sub.3)CO.sub.2 Na,                                        CF(CF.sub.3)OOCF═CF.sub.2                                                 and copolymer with                                                            TFE                                                             13   CH.sub.3 SO.sub.2                                                                  F   CF(CF.sub.3)OCF.sub.2 CF═CF.sub.2                                                        --                                                                               --   --                                       __________________________________________________________________________

EXAMPLE 1 4-Phenoxyheptafluorobutanone-2 ##STR3##

Phenyl trifluoroacetate, bp 53°-55° (20 mm, 2.7 kPa) was prepared in 95%yield as described by Hudlicky in "Chemistry of Organic FluorineCompounds," Wiley, New York, 1976, p. 708 Sodium phenoxide was preparedas described by N. Kornblum and A. P. Lurie, J. Am. Chem. Soc., Volume81, 2705 (1959).

A mixture of 46.4 g (0.40 mol) of anhydrous sodium phenoxide, 90.6 g(0.48 mol) of phenyl trifluoroacetate, 150 mL of DMSO, and 50 g (0.50mol) of tetrafluoroethylene was shaken in a 400-mL tube at about 30° to35° for 8 hours during which time the pressure dropped from greater than400 psi (675 kPa) to about 130 psi (220 kPa). The temperature wasincreased to about 50° at which the pressure was about 140 psi (235kPa), for two more hours after which the pressure was about 135 psi (230kPa). The reaction mixture was poured into a solution of 200 mL ofconcentrated HCl in 1 liter (L) of ice water. A lower layer was washedwith a solution of 50 mL of concentrated HCl in 500 mL of water and thenwith 500 mL of water to give 135.3 g of oil. The oil was stirredovernight with 258 g (1.23 mol) of trifluoroacetic anhydride in anattempt to remove all the water. Fractionation yielded 91 g of a mixturecontaining both 4-phenoxyheptafluorobutanone-2 and its hydrate, bp 25°(10 mm, 1.3 kPa) -42° (1 mm, 0.1 kPa). This crude produce was dissolvedin 50 mL of CFCl₂ CF₂ Cl and stirred with 30 g. The CFCl₂ CF₂ Clsolution was decanted and the product was stirred with an additional 10g of P₂ O₅. The organic layer was decanted and distilled to afford 54.2g (47%) of 4-phenoxyheptafluorobutanone-2, bp 70°-74° (40 mm, 5.3 kPa).IR (CFl₄): 3080 (arom CH), 1790 (C═O), 1600, 1590, and 1490 (arom C═C),and 1250-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 7.23 ppm (m, arom CH), ¹⁹F-75.4 (t of t, J_(FF) 8.3, 2.5 Hz, 3F, CF₃), -84.6 (t of q, J_(FF) 4.7,2.5 Hz, 2F, OCF₂) and -118.1 ppm (q of t, J_(FF) 8.3, 4.7 Hz, 2F, CF₂C═O).

Anal. Calcd for C₁₀ H₅ F₇ O₂ : C, 41.40; H, 1.74. Found: C, 41.71; H,1.90.

EXAMPLE 2 4-Phenoxy-3-trifluoromethoxyhexafluorobutanone-2 ##STR4##

A 400-mL tube was charged with 46.4 g (0.40 mol) of sodium phenoxide,90.6 g (0.48 mol) of phenyl trifluoroacetate, 150 mL of DMSO, and 83 g(0.50 mol) of perfluoro (methyl vinyl ether). The tube was shaken at 25°for 8 h, then at 50° for 2 h. The reaction mixture was poured into asolution of 200 mL of concentrated HCl in 1 L of ice water, and aproduct layer was extracted with a solution of 50 mL of concentrated HClin 500 mL of water. The aqueous layer was extracted twice with ether,and the ether extracts were evaporated to give additional crude product.The combined products were diluted with benzene, and water (12 mL) wasazeotroped off. The clear benzene solution was stirred with 142 g (1.0mol) of P₂ O₅ until an exotherm had subsided. The solution was left tostand overnight, and then heated to reflux. The benzene solution wasdecanted and distilled to afford 47.2 g (33%) of4-phenoxy-3-trifluoromethoxyhexafluorobutanone-2, bp 61°-70° (5 mm, 0.6kPa). A fraction containing only minor impurity by GC was analyzed. IR(CCl₄): 3080 (arom. CH), 1790 (C═O), 1595 and 1495 (arom. C═C), and1300-1100 cm⁻¹ (CF, C--O). NMR (CCl₄); ¹ H 7.2 ppm (m,, arom. CH); ¹⁹ F-55.0 (d of q, J_(FF) 9.2, 2.6 Hz, 3F, OCF₃), -74.7 (d of sextets,J_(FF) 14.0, 3 Hz, 3F, CF₃ C═O), and -138.2 ppm (q of p, J_(FF) 14.0, 9Hz, 1F, CF) with an AB for CF₂ O at -7652 and -7790 Hz (q, J_(FF) 3.4Hz, 1F) and -7885 and -8022 Hz (d of q, J_(FF) 9.1, 3.4 Hz, 1F).

Anal. Calcd for C₁₁ H₅ F₉ O₃ : C, 37.09; H, 1.42; F, 48.01. Found: C,37.00; H, 135; F, 48.18.

EXAMPLE 3 4-Methylthioheptafluorobutanone-2 ##STR5##

A suspension of 24.0 g (0.50 mol) of 50% NaH/mineral oil in 150 mL oftetrahydrofuran was treated with 2 g (0.01 mol) of trifluoroethyltrifluoroacetate to serve as catalyst for salt formation. The mixturewas then stirred at 25°-40° while 24.0 g (0.50 mol) of methyl mercaptanwas distilled in. The mixture was stirred until evolution of gas througha -80° condenser had ceased (2 h). The mixture was cooled in anice-water bath while 117.6 g (0.60 mol) of trifluoroethyltrifluoroacetate was added. A 400-mL tube charged with the above mixtureand 50 g (0.50 mol) of tetrafluoroethylene was agitated for 6 h whilethe temperature rose to 36°, then for 1 h at 50°. Volatiles were removedfrom the reaction mixture under reduced pressure, and the residue wastreated and stirred successively with 50 mL of ether, 50 g ofconcentrated HCl, and 21.0 g of NaHCO₃. When gas evolution ceased afterthe last addition, the mixture was filtered and the moist solids wererinsed with ether. Fractionation of the combined filtrates afforded109.8 g of crude 4-methylthioheptafluorobutanone-2 hydrate containingsome tetrahydrofuran, bp 65°-68° (90 mm, 12.0 kPa).

The crude product was stirred for 6 h with 30 mL of CFCl₂ CF₂ Cl and 100g of P₂ O₅. Then volatiles were transferred under vacuum at 25° andfractionated. The first product fraction, 56.3 g of crude4-methylthioheptafluorobutanone-2, bp 86°-94°, was redistilled to give40.2 g (33) of pure 4-methylthioheptafluorobutanone-2, bp 57°-60° (200mm, 26.6 kPa). IR (CCl₄): 3010, 2940, and 2850 (sat'd CH); 1785 (C═O),1250-1100 cm⁻¹ (CF). NMR (CCl₄): ¹ H 2.37 ppm (t of t, J_(HF) 1.3, 0.9Hz, CH₃ S); ¹⁹ F -75.6 (t of t, J_(FF) 8.4, 4.2 Hz, 3F, CF₃), -91.7 (tof q of m, J_(FF) 5.8, 4.2 Hz, 2F, CF₂ S), and -116.6 ppm (q of t of m,J_(FF) 8.4, 5.8 Hz, 2F, CF₂). Mass spec (E.I.): m/e 243.9794, M⁺ (calcdfor C₅ H₃ F₇ OS, 243.9793); 224.9873, M⁺ -F (calcd 224.9808); 205.9938,M⁺ -2F (calcd 205.9825); 196.9808, M⁺ -CH₃ S (calcd 196.9837).

Anal. Calcd for C₅ H₃ F₇ OS: C, 24.60; H, 1.24. Found: C, 24.97; H,1.48.

Further distillation of the material which had been treated with P₂ O₅gave 16.2 g (10%) of 4-methylthioheptafluorobutanone-2 hydrate ° 5/6tetrahydrofuran, bp 70° (100 mm, 13.3 kPa). IR (neat): 3100 (broad,H-bonded OH), 2980 and 2880 (sat'd CH), and 1300-1100 cm⁻¹ (CF, C--O).NMR (CCl₄): ¹ H 5.58 (s, 2H, OH) and 2.36 ppm (s, 3H, CH₃ S) with bandsfor 5/6 THF at 3.78 (CH₂ O) and 1.89 ppm (CH₂).

Anal. Calcd for C₅ H₅ F₇ O₂ S.sub.° 5/6C₄ H₈): C, 3.106; H, 3.65. Found:C, 31.11; H, 3.81.

EXAMPLE 4 1-Methoxy-5-methylthiooctafluoropentanone-3 ##STR6##

A mixture of 24 g (0.50 mol) of 50% NaH/mineral oil and 150 mL oftetrahydrofuran was stirred under a -80° condenser while 24.0 g (0.50mol) of methyl mercaptan was distilled in. Gas evolution subsidedquickly but resumed upon addition of 2.0 g (0.01 mol) of trifluoroethyltrifluoroacetate. After stirring overnight, the mixture was cooled to 0°and added to a 400-mL tube along with 114.0 g (0.60 mol) of cold methyl3-methoxytetrafluoropropionate. The mixture was agitated at 10° while 50g (0.50 mol) of tetrafluoroethylene was injected. An exotherm to 26° wasfollowed by a reaction period of 20 h at 10°. The reaction mixture wasacidified with 50 g (0.5 mol) of concentrated HCl and warmed to 30° (40mm, 5.3 kPa) to remove volatiles. A residual oil and solid mixture wasextracted with 2×200 mL ether, and the extracts were stirred with excessNaHCO₃ until gas evolution ceased. The ether solution was then driedover CaSO₄, extracted with ether and distilled to afford 41.0 g (27%) of1-methoxy-5-methylthiooctafluoropentanone-3, bp 65°-66° (66 mm, 0.8kPa). IR (neat): 3010, 2960 and 2860 (sat'd CH), 1775 (C═O), and1250-110 cm⁻¹ (CF, C--O). Mass spec. (E.I.): m/e 305.9950, M⁺ (calcd forC₇ H₆ F₈ O₂ S, 305.9960); 286,9960, M⁺ -F (calcd 286.9977); 159.0078,CH₃ OCF₂ CF₂ CO (calcd 159.0069); 146.9890, CH₃ SCF₂ CF₂ ⁺ (calcd146.9891); 131.0096, CH₃ OCF₂ CF₂ ⁺ (calcd 131.0119).

EXAMPLE 56-Azido-4-hydroxy-4-trifluoromethyl-1,1,1,5,5,6,6-heptafluoro-3-oxahexane,sodium salt ##STR7##

A 400-mL tube was charged with 26.0 g (0.40 mol) of sodium azide, 98.0 g(0.50 mol) of trifluoroethyl trifluoroacetate, 150 mL of DMSO, and 40 g(0.40 mol) of tetrafluoroethylene. The tube was skaken at ambienttemperature (about 30°) for 4 h, then at 50° for 4 h. Pressure readingsindicated that the reaction was substantially complete at 30°.

To demonstrate that the product was N₃ CF₂ CF₂ C(ONa) (OCH₂ CF₃)CF₃, thereaction mixture was stirred overnight with 56.7 g (0.45 mol) ofdimethyl sulfate, then heated to 40° (0.5 mm, 0.1 kPa) to removevolatiles. Fractionation of the volatiles gave 101.4 g (72%) of6-azido-4-methoxy-4-trifluoromethyl-1,1,1,5,5,6,6-heptafluoro-3-oxahexane, bp 60°-61° (15 mm, 2.0 kPa). IR (CCl₄): 3010, 2970,and 2660 (sat'd CH), 2150 (N₃), 1300-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹H 4.10 (q, J_(FF) 7.8 Hz, 2H, CH₂ CF₃) and 3.67 ppm (s, 3H, OCH₃); ¹⁹ F-73.8 (t of t, J_(FF) 9.3, 7.9 Hz, 3F, CF₃), -75.3 (t, J_(HF) 7.8 Hz,3F, CF₃ CH₂), -89.3 (q of t, J_(FF) 7.9, 3.4 Hz, 2F, CF₂ N₃), and 117.7ppm (q of t, J_(FF) 9.3, 3.4 Hz, CF₂).

Anal. Calcd for C₇ H₅ F₁₀ N₃ O₂ : C, 23.81; H, 1.43; N, 11.90. Found: C,23.89; H, 1.43; N, 12.00.

EXAMPLE 6 4-Azidoheptafluorobutanone-2 ##STR8##

Sodium azide, trifluoroethyl trifluoroacetate and tetrafluorethylenewere mixed and reacted, as in Example 6, at ambient temperature(exotherm to 34°) for 4 h and then at 50° for 1 h. After several weeks,the reaction mixture was stirred into a solution of 300 mL ofconcentrated HCl in 1 L of ice water. The mixture was extractedcontinuously with ether for one day. The extracts were distilled untilthe pot temperature reached 60°. The residue from the distillation wasdivided into portions. A 25 mL portion was added dropwise to 50 mL ofconcentrated H₂ SO₄ at 10°, stirred for an additional 30 min andevacuated at 10 m (1.3 kPa). To a 250 mL-portion, 600 mL of concentratedH₂ SO₄ was added dropwise. The mixture was stirred for 1 h and thenevacuated at 10 mm (1.3 kPa). The combined product was 83.7 g (88%) of4-azidoheptafluorobutanone-2, pure by GC. IR (CCl₄): 2150 (N₃), 1790(C═O), and 1250-1100 cm⁻¹ (CF). NMR (CCl₄): ¹⁹ F -75.6 (t of t, J_(FF)8.3, 2.9 Hz, 3F, CF₃), -89.9 (m, 2F, CF₂ N₃), and -120.8 (q of t, J_(FF)8.3, 4.5 Hz, 2F, CF₂ C═O). An analytical sample was distilled from P₂O₅, bp 64°.

Anal. Calcd for C₄ F₇ N₃ O: C, 20.10; N, 17.58. Found: C, 20.20; N,17.59.

EXAMPLE 7 1-Azidononafluoropentanone-3 ##STR9##

Trifluoroethyl pentafluoropropionate, bp 70°, was prepared in 79% yieldby reaction of equimolar amounts of trifluoroethanol,pentafluoropropionyl chloride, and pyridine in diglyme. IR (CCl₄): 2970(sat'd CH), 1800 (C═O), and 1300-1150 cm⁻¹ (CF, C--O).

A mixture of 26.0 g (0.40 mol) of sodium azide, 102 g (0.41 mol) oftrifluoroethyl pentafluoropropionate, 150 mL of DMSO, and 40 g (0.40mol) of tetrafluoroethylene was reacted in a 400-mL tube for 6 h at roomtemperature (22° to 34°). The reaction mixture was cooled and stirredwhile 57 g (0.50 mol) of trifluoroacetic acid was added. Then 25 mL ofether was added, and the whole heated slowly to 53° at 1.4 mm (0.2 kPa).Volatile product so obtained was diluted with 75 mL of ether anddistilled until the head temperature reached 40°. The residue was cooledand stirred with 250 mL of concentrated H₂ SO₄ for 2 h, then evacuatedat 1.6 mm (0.2 kPa) at room temperature to give 102.1 g (88%) of1-azidononafluoropentanone-3, nearly pure by GC. IR (CCl₄): 2140 (N₃),1780 (C═O), and 1300-1100 cm⁻¹ (CF). NMR (CCl₄): ¹⁹ F -82.4 (t, J_(FF)3.1 Hz, 3F, CF₃), -89.8 (p, J_(FF) 4.5 Hz, 2F, CF₂ N₃), -120.0 (m, 2F,CF₂), and -121.4 ppm (t of d of q, J_(FF) 11.8, 4.5, 1 Hz, 2F, CF₂).

EXAMPLE 8 1-Methoxy-5-azidooctafluoropentanone-3 ##STR10##

Trifluoroethyl 3-methoxytetrafluoropropionate was prepared by reactionof 97.3 g (0.50 mol) of 3-methoxytetrafluoropropionyl chloride, 55.0 g(0.55 mol) of trifluoroethanol, and 39.5 g (0.50 mol) of pyridine in 100mL methylene chloride. Reaction was extremely slow until the pyridinewas added. After having stirred overnight, the reaction mixture wasfiltered, solids were rinsed with methylene chloride, and filtrates weredistilled to give 119.4 g of ester, bp 44°-49° (20 mm, 2.7 kPa). Thecloudy product was treated with 2 g of P₂ O₅ and filtered to afford109.3 g (93%) of the desired ester, pure by GC. IR (CCl₄): 2855, 2975,and 3010 (sat'd CH), 1790 (C═O), and 1300-1100 cm⁻¹ (CF, C--O).

A 400-mL tube was charged with 26.0 g (0.40 mol) of sodium azide, 109 g(0.42 mol) of trifluoroethyl 3-methoxytetrafluoropropionate, 150 mL ofDMSO, and 40 g (0.40 mol) of tetrafluoroethylene and was agitated at24°-37° for 6 h, then at 40° for 2 h. The reaction mixture was pouredinto 300 mL of concentrated HCl and 1 L of water. A lower layer wasseparated and an aqueous layer was extracted with 250 mL, and then with100 mL, of ether. The combined organic layers were washed with 100 mL ofwater, dried over CaSO₄, and distilled to afford 78.7 g (65%) of1-azido-5-methoxyoctafluoropentanone-3, bp 62° (40 mm, 5.3 kPa). IR(CCl₄): 3010, 2960, and 2860 (sat'd CH), 2145 (N₃), 1775 (C═O), and1250-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 3.72 ppm (s, CH₃ O); ¹⁹F-90.1 (p, J_(FF) 4 Hz, 2F, CF₂), -90.3 (p, J_(FF) 4 Hz, 2F, CF₂),-119.8 (m, 2F, CF₂), and -210.8 ppm (m, 2F, CF₂).

Anal. Calcd for C₆ H₃ F₈ N₃ O₂ : C, 23.93; H, 1.00; N, 13.96. Found: C,23.77; H, 1.01; N, 13.89.

EXAMPLE 9 1,9-Bisazidododecafluoro-5-oxanonane-3,7-dione ##STR11##

Crude tetrafluorodiglycolic acid hydrate (129 g, 0.6 mol), obtained bypermanganate oxidation of3,4-dichloro-2,2,5,5-tetrafluoro-2,5-dihydrofuran, was stirred with 130g (1.3 mol) of trifluoroethanol and 200 mL of concentrated H₂ SO₄ at 25°for 4 days. The upper layer was extracted with 25 mL of concentrated H₂SO₄, clarified with CaSO₄, and distilled to give 130.8 g (59%) ofbis(trifluoroethyl)tetrafluorodiglycolate, bp 85°-86° (20 mm, 2.7 kPa).IR (neat): 2985 (sat'd CH), 1810 (C═O), 1250-110 cm⁻¹ (CF, C--O). NMR(CCl₄); ¹ H 4.63 ppm (q, J_(HF) 7.8 Hz, CH₂ CF₃); ¹⁹ F -69.6 (t, J_(HF)7.8 Hz, 6F, CF₃ CH₂) and -77.7 ppm (s, 4F, CF₂ O).

A 400-mL tube was charged with 66.6 g (0.18 mol) ofbis(trifluoroethyl)tetrafluorodiglycolate, 11.7 g (0.18 mol) of sodiumazide, 150 mL of DMSO, and 20 g (0.20 mol) of tetrafluoroethylene andwas agitated at 25°-34° for 6 h, then at 40° for 2 h. The reactionmixture was poured into 300 mL of concentrated HCl in 1 L of water. Alower layer was removed and an aqueous phase was extracted with 2X 250mL of ether. The combined organic layers were washed with 100 mL ofwater and dried over CaSO₄. Distillation produced 5.5 g (13% based onNaN₃) of 1,9-bisazidododecafluoro-5-oxanonane-3,7-dione, bp 45° (0.5 mm,0.1 kPa). Analytical data indicated the presence of an impuritycontaining a CF₃ CH₂ O-group. IR (neat): 2160 (N₃), 1790 (C═O), and1300- 1100 cm⁻¹ (CF, C--O). NMR (CD₃ CN): ¹ H traces --OCH₂ CF₃ ; ¹⁹ F-76.7 (m, 4F, CF₂ O), -89.1 (m, 4F, CF₂ N₃), and -119.2 ppm (roughseptet, J_(FF) 4.5 Hz, 4F, CF₂ C═O).

Anal. Calcd for C₈ F₁₂ N₆ O₃ : C, 21.07; N, 18.43. Found: C, 20.75; N,17.33.

EXAMPLE 10 1,5-Bisazidooctafluoropentanone-3 ##STR12##

Trifluoroethyl 3-azidotetrafluoropropionate was prepared by treatment ofmethyl 3-azidotetrafluoropropionate with excess trifluoroethanol andconcentrated H₂ SO₄ at 25° for 4 days. Product, bp 58°-60° (50 mm, 6.7kPa) was isolated in 55% yield by evaporation of volatiles from thesulphuric acid followed by fractionation. IR (CCl₄): 2970 (sat'd CH),2140 (N₃), 1795 (C═O), and 1300-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H4.68 ppm (q, J_(HF) 7.8 Hz, CH₂ CF₃) with a small amount of N₃ CF₂ CF₂CO₂ CH₃ indicated as impurity: ¹⁹ F -74.8 (t, J_(HF) 7.8 Hz, 3F, CF₃CH₂), -91.3 (t, J_(FF) 4.7 Hz, 2F, CF₂ N₃), and -120.8 ppm (t, J_(FF)4.7 Hz, 2 F, CF₂ C═O).

Anal. Calcd for C₅ H₂ F₇ N₃ O₂ : C, 22.32; H, 0.75; N, 15.62. Found: C,22.57; H, 0.95; N, 16.24.

A 400-mL tube was charged with 49.4 g (0.18 mol) of trifluoroethyl3-azidotetrafluoropropionate, 150 mL of DMSO, 12.0 g (0.18 mol) ofsodium azide, and 18 g (0.18 mol) of tetrafluoroethylene and wasagitated at 25° for 6 h, then at 40° for 2 h. The reaction mixture waspoured into 250 mL of concentrated HCl in 1 L of water. The resultingmixture was extracted with 4×200 mL of ether, the combined ethersolutions were washed with 500 mL of water, dried over P₂ O₅, and theether was distilled off. Product was removed from the residue undervacuum, dried over CaSO₄ and fractionated to afford 20.5 g (39%) of1,5-bisazidooctafluoropentanone-3, bp 50°-51° (25 mm, 3.3 kPa). IR(CCl₄): 2140 (N₃), 1770 (C═O), and 1300-1100 cm⁻¹ (CF). NMR (CCl₄): ¹⁹ F-89.8 (s, 2F, CF₂ N₃) and -119.9 ppm (s, 2F, CF₂ ═O). Mass spec (C.I.):m/e 293 (M⁺ -F), 265 (M⁺ -F-N₂), 237 (M⁺ -F-2N₂), 170 (N₃ CF₂ CF₂ CO⁺),142 (N₃ CF₂ CF]2⁺), 114 (C₂ F₄ N⁺), 100 (C₂ F₄ ⁺), 92 (N₃ CF₂ ⁺) withother unexplained bands present.

Anal. Calcd for C₅ F₈ N₆ O: C, 19.24; N, 26.93. Found: C, 19.22; N,25.97.

EXAMPLE 11 4-Methylsulfonylheptafluorobutanone-2 ##STR13##

A solution of 26.8 g (0.11 mol) of 4-methylthioheptafluorobutanone-2 in25 mL of acetic acid was stirred at 90° while a mixture of 23.0 mL (25.5g, 0.23 mol) of 30% hydrogen peroxide and 20 mL of acetic acid was addedover 30 min. The mixture was stirred at 90°-95° for an additional 3 hand distilled to give 22.9 g (71%) of4-methylsulfonylheptafluorobutanone-2 hydrate, bp 98°-100° (50 mm, 6.7kPa). IR (neat): 3440 (broad, OH), 2940 (sat'd CH), 1350 (SO₂), and1250-1050 cm⁻¹ (CF, CO, SO₂). NMR (acetone-d₆): ¹ H 7.71 (broad s, 2H,OH) and 3.26 ppm (s, 3H, CH₃ SO₂); ¹⁹ F -81.2 (t of t, J_(FF) 10.8, 5Hz, 3F, CF₃), -112.7 (m, 2F, CF₂), and -119.2 ppm (m, 2F, CF₂).

Anal. Calcd for C₅ H₅ F₇ O₄ S: C, 20.42; H, 1.17. Found: C, 20.86; H,2.19. ##STR14##

4-Methylsulfonylheptafluorobutanone-2 hydrate (17.4 g, 0.059 mol) wasadded to 31.2 g (0.20 mol) of P₂ O₅ and heated to 100°. Distillationthen gave 13.3 g (82%) of 4-methylsulfonylheptafluorobutanone-2, bp85°-110° (100 mm, 13.3 kPa). IR (CCl₄): 3040, 3020, and 2940 (sat'd CH),1790 (C═O), 1370 (SO₂), and 1300-1100 (CF, SO₂). NMR (CD₃ CN): ¹ H 3.27ppm (t of t, J_(HF) 1.8, 0.5 Hz, CH₃ SO₂); ¹⁹ F -74.3 (t of t, J_(FF)8.4, 3.5 Hz, 3F, CF₃), -114.8 (m, 2F, CF₂ SO₂), and -117.4 ppm (q of t,J_(FF) 8.4, 4.2 Hz, 2F, CF₂ C═O).

Anal. Calcd for C₅ H₃ F₇ O₃ S: C, 21.75; H, 1.09. Found: C, 21.84; H,1.46.

EXAMPLE 12 9-Azido-perfuoro-2,5,7-trimethyl-3,6-dioxananoyl Fluoride##STR15##

A suspension of 4.0 g (0.068 mol) of flame-dried KF in 400 mL oftetraglyme was stirred at 25° while a solution of 79.0 g (0.33 mol) of4-azidoheptafluorobutanone-2 in 100 mL of tetraglyme was added. Themixture was further stirred at 15°-25° while 113 g (0.68 mol) of HFPOwas distilled in over a 5 h period. The mixture was stirred, untilcondensation in a -80° condensor ceased, and then heated under vacuum to50° (0.1 mm, 0 kPa) while 126.3 g of volatiles was removed.Fractionation gave 47.4 g (35%) of crude 1:1 adduct, bp 58°-62° (80 mm,10.7 kPa), and 50.5 g (27%) of 2:1 adduct, perfluoro(9-azido-2,5,7-trimethyl-3,6-dioxanonanoyl) fluoride, bp 58°-59° (8 mm,1.1 kPa). For the 2:1 adduct, IR (CCl₄): 2150 (N₃), 1880 (COF), 1300-110cm⁻¹ (CF, C--O). NMR (CCl₄): ¹⁹ F fits a mixture of racemates of N₃ CF₂CF₂ CF(CF₃)OCF(CF₃)CF₂ OCF(CF₃)COF.

Anal. Calcd for C₁₀ F₁₉ N₃ O₃ : C, 21.03; N, 7.36. Found C, 21.12; N,7.84.

Washing of the high-boiling residue from evaporation of volatileproducts and distillation of water-insoluble product gave 25.0 g (10%)of 3:1 adduct as the carboxylic acid, bp 56°-58° (0.03 mm, 0 kPa).##STR16##

A 22.8 g (0.04 mol) sample of the above 2:1 adduct was stirred with 75mL of water and a few drops of phenolphthalein while aqueous NaOHsolution was added dropwise to a permanent endpoint. Most of the waterwas then evaporated in a stream of air, and a residual moist cake wasdried by heating it slowly to 140° (0.1 mm, 0 kPa). Further heating ofthe dry salt to 220° caused the pressure to rise to 1.8 mm (0.2 kPa).The pyrolysis was carried out at 220°-223° until the pressure dropped to0.3 mm (0 kPa) after 12 h. The crude product, 16.9 g, was dried anddistilled to afford 8.0 g (40%) of perfluoro(9-azido-5,7-dimethyl-3,6-dioxanonene-1), bp 64°-66° (20 mm, 2.7 kPa),only very minor impurities by GC. IR (neat): 2150 (N₃), 1840 (C═C),1300-1100 cm⁻¹ (CF, CO). NMR (CCl₄): ¹⁹ F compatible with N₃ CF₂ CF₂CF(CF₃)OCF(CF₃)CF₂ OCF═CF₂.

Anal. Calcd for C₉ F₁₇ N₃ O₂ : C, 21.40; N, 8.32. Found: C, 21.58; N,8148. ##STR17##

A mixture of 16.7 g (0.033 mol) of the above trifluorovinyl ether, 20 mLof CFCl₂ CF₂ Cl, and 2 mL of 3% perfluoropropionyl peroxide in CFCl₂ Clwas shaken in a 100 mL stainless steel-lined tube at 25°-30° with about200 psi (1.4 MPa) of tetrafluoroethylene. The tube was repressured withtetrafluoroethylene as needed until 30 g (0.30 mol) had been added. Thereaction was continued for an additional 1.5 h. A moist solid polymerwhich was produced was dried to constant weight under vacuum to give16.1 g white solid copolymer. IR (nujol): 2160 (N₃) and 1250-1150 cm⁻¹(CF, C--O).

EXAMPLE 13 7-Methylsulfonylperfluoro-5-methyl-4-oxaheptene-1 ##STR18##

A mixture of 12.76 g (0.046 mol) of4-methylsulfonylheptafluorobutanone-2, 2.91 g (0.05 mol) of flame-driedKF, and 100 mL of diglyme was stirred for 15 min. Stirring was continuedat 0°-5° while 10.6 g (0.046 mol) of perfluoroallyl fluorosulfate wasadded dropwise. The mixture was stirred at 0°-5° for another 2 h andthen poured into 500 mL of cold water. The lower layer was washed with100 mL of water, dried over CaSO₄, and fractionated to give 4.3 g (22%)of 7-methylsulfonyl-5-trifluoromethyl-4-oxadecafluoroheptene-1, bp 83°(1.9 mm, 0.3 kPa). IR (neat): 3040, 3020, and 2930 (sat'd CH), 1790(C═C), 1380 (SO₂), and 1250-110 cm⁻¹ (CF, C--O). Proton and ¹⁹ F NMRspectra support the assigned structure.

Anal. Calcd for C₈ H₃ F₁₃ O₃ S: C, 22.55; H, 0.71. Found: C, 22.26; H,0.84.

I claim:
 1. The β-substituted polyfluoroethyl compound having theformula,

    N.sub.3 CF.sub.2 CFYZ,

wherein Y is --F, --Cl or --OR_(F) ¹ ; Z is selected from --C(O)R_(F)X¹, --CF(R_(F) X¹)O--CF(CF₃)CF₂ O--_(n) CF(CF₃)COF, --CF(R_(F)X¹)O--CF(CF₃)CF₂ O --_(n) CF(CF₃)CO₂ M¹, --CF(R_(F) X¹)O--CF(CF₃)CF₂O--_(n) CF═CF₂, --CF(R_(F) X¹)O--CF(CF₃)CF₂ O--_(m) CF₂ CF═CF₂, and Z¹R_(F) Z¹ CFYCF₂ N₃ ; R¹ is C₁₋₁₀ alkyl, C₆₋₁₀ aryl or C₆₋₁₀ aralkyl;R_(F) ¹ is C₁₋₄ perfluoroalkyl; R_(F) is --CF₂ -- or C₂₋₈perfluoroalkylene, or C₂₋₈ perfluoroalkylene containing one in-chainether oxygen bond, or two in-chain ether oxygen bonds separated by atleast two carbon atoms; M¹ is an alkali metal, alkaline earth metal orammonium; n is 0 to 6; m is 0 to 7; Z¹ is --C(O)--, --CF(O--CF(CF₃)CF₂O--_(n) CF(CF₃)COF)--, --CF(O--CF(CF₃)CF₂ O--_(n) CF(CF₃)CO₂ M¹)--,--CF(O--CF(CF₃)CF₂ O--_(n) CF═CF₂)--, or --CF(O--CF(CF₃)CF₂ O--_(m) CF₂CF═CF₂)--; and X¹ is --F, --SR¹, --SO₂ R¹, --CO₂ R, --N₃ or --OR² ; R is--CH₂ CF₃, --CH₂ (CF₂ CF₂).sub.(1-6) H, --C₆ H₅ or C₁₋₃ alkyl; and R² is--CH₃, --C₂ H₅ or --C₆ H₅.
 2. The compound of claim 1 wherein Z is--C(O)R_(F) X¹ or --C(O)R_(F) C(O)CFYCF₂ N₃.
 3. The compound of claim 2wherein X¹ is --F, --N₃, --CO₂ R or --OCH₃ ; and Y is --F or --OCF₃. 4.The compound of claim 3 wherein R_(F) is --CF₂ --, --CF₂ CF₂ -- or --CF₂OCF₂ --; R is --CH₃ or --CH₂ CF₃ ; and R¹ is --CH₃, --C₂ H₅ or --C₆ H₅.5. The compound of claim 4 wherein X¹ is --F.
 6. The compound of claim 4wherein X¹ is --CO₂ R.
 7. The compound of claim 4 wherein X¹ is --N₃. 8.The compound of claim 4 wherein X¹ is --OCH₃.
 9. The compound of claim 1whereinY is --F or --OCF₃ ; Z is selected from --COCF₃, --COC₂ F₅,--COCF₂ CF₂ OCH₃, --COCF₂ OCF₂ COCF₂ CF₂ N₃, --CF(CF₃)O--CF(CF₃)CF₂O--CF(CF₃)COF, --CF(CF₃)O--CF(CF₃)CF₂ O--CF(CF₃)CO₂ M¹,--CF(CF₃)O--CF(CF₃)CF₂ O--CF═CF₂, --CF(CF₃)OCF₂ CF═CF₂.
 10. The compoundof claim 9 wherein Z is --COCF₃.
 11. The compound of claim 9 wherein Zis --COC₂ F₅.
 12. The compound of claim 9 wherein Z is --COCF₂ CF₂ OCH₃.13. The compound of claim 9 wherein Z is --CF(CF₃)O--CF(CF₃)CF₂O--CF(CF₃)COF.
 14. The compound of claim 9 wherein Z is--CF(CF₃)O--CF(CF₃)CF₂ O--CF═CF₂.
 15. The compound of claim 9 wherein Zis --CF(CF₃)OCF₂ CF═CF₂.
 16. The compound of claim 9 wherein Z is--CF(CF₃)O--CF(CF₃)CF₂ O--CF(CF₃)CO₂ M¹.
 17. The compound N₃ CF₂CFYC(OM)(OR)R_(F) X⁴, whereinY is --F, --Cl or --OR_(F) ¹ ; M is analkali metal; R is --CH₂ CF₃, --CH₂ (CF₂ CF₂).sub.(1-6) H, --C₆ H₅ orC₁₋₃ alkyl; R¹ is C₁₋₁₀ alkyl, C₆₋₁₀ aryl or C₆₋₁₀ aralkyl; R_(F) ¹ isC₁₋₄ perfluoroalkyl; R_(F) is --CF₂ -- or C₂₋₈ perfluoroalkylene, orC₂₋₈ perfluoroalkylene containing one in-chain ether oxygen bond, or twoin-chain ether oxygen bonds separated by at least two carbon atoms; X⁴is X¹ or --C(OR)(OM)CFYCF₂ N₃ ; and X¹ is --F, --SR¹, --SO₂ R¹, --CO₂ R,--N₃ or --OR² and R² is --CH₃, --C₂ H₅, or --C₆ H₅.
 18. The compound ofclaim 17 whereinY is --F or --OCF₃ ; M is Na; R is --C₆ H₅, --CH₂ CF₃,or --CH₃ ; R_(F) is --CF₂ --, --CF₂ CF₂ --, or --CF₂ OCF₂ --; and X⁴ is--F, --OCH₃, --N₃, or --(ONa)(OCH₂ CF₃)CCF₂ CF₂ N₃.
 19. A process forpreparing a compound of claim 17 comprising reacting a polyfluoroolefin,CF₂ ═CFY, with a metal salt, MN₃, and a fluoroester, X¹ R_(F) CO₂ R,wherein Y, M, R_(F), X⁴, X¹ and R are as defined in claim
 17. 20. Aprocess according to claim 19 wherein M is sodium.
 21. A process forpreparing a compound of claim 1 wherein Z is --C(O)R_(F) X¹ or Z¹ R_(F)Z¹ CFYCF₂ N₃ where Z¹ is --C(O)--, comprising treating the compound ofthe formula

    N.sub.3 CF.sub.2 CFYC(OM)(OR)R.sub.F X.sup.4

with a mineral acid, wherein Y is --F, --Cl, or --OR_(F) ¹ ; M is analkali metal; R is --CH₂ CF₃, --CH₂ (CF₂ CF₂).sub.(1-6) H, --C₆ H₅ orC₁₋₃ alkyl; R¹ is C₁₋₁₀ alkyl, C₆₋₁₀ aryl or C₆₋₁₀ aralkyl; R_(F) ¹ isC₁₋₄ perfluoroalkyl; R_(F) is --CF₂ -- or C₂₋₈ perfluoroalkylene, orC₂₋₈ perfluoroalkylene containing one in-chain ether oxygen bond, or twoin-chain ether oxygen bonds separated by at least two carbon atoms; X⁴is X¹ or --C(OR)(OM)CFYCF₂ N₃ ; X¹ is --F, --SR¹, --SO₂ R¹, --CO₂ R,--N₃ or --OR² ; and R² is --CH₃, --C₂ H₅ or --C₆ H₅.
 22. A process forpreparing the compound of claim 1 N₃ CF₂ CFYCF(R_(F) X¹)O--CF(CF₃)CF₂O--_(n) CF═CF₂, which comprises pyrolyzing the compound, N₃ CF₂CFYCF(R_(F) X¹)O--CF(CF₃)CF₂ O--_(n) CF(CF₃)COF, in an aprotic solventin the presence of a carbonate, phosphate, sulfite or sulfate salt of analkali or alkaline earth metal.
 23. A process for preparing the compoundof claim 1 N₃ CF₂ CFYCF(R_(F) X¹)O--CF(CF₃)CF₂ O--_(n) CF═CF₂, whichcomprises pyrolyzing at reduced pressure the compound, N₃ CF₂CFYCF(R_(F) X¹)O--CF(CF₃)CF₂ O--_(n) CFCF₃ CO₂ M¹.